Flexible Printed Circuits Board (Flex PCB)

Flexible Printed Circuits Boards (FPCB) (also referred as flex circuits, FPC, flex print, flex-circuits) consist of a thin insulating polymer film with circuit patterns affixed thereto and typically covered with a thin polymer coating to protect the circuits.
FPC has been applied for interconnecting electronics since the 1950s.
It's now one of the most essential interconnection technologies used for today's most advanced electronic products.

There are several kinds of flexible circuits, including one layer, double sided, multilayer and rigid flex PCB.
These circuits can be made by etching metal foil cladding (copper) from polymer bases, printing of conductive inks or plating metal among other processes.
Flexible circuits may or may not have components mounted. When components are mounted, they are considered flexible electronic assemblies.